There are many different types of beauty serums, but if we had to pick just one to include in every skin care routine, it would be vitamin C. Vitamin C serums effectively tackle a multitude of skin issues, from aging to sun damage.

Since serums penetrate deep into the skin, they can help supercharge any beauty regimen with a high concentration of active ingredients. Jana Blankenship, founder of organic beauty line Captain Blankenship, says vitamin C serums are especially important because they help firm skin, improve texture and tone, and combat the signs of aging. Elizabeth Jones, advanced instructor for Dermalogica and the International Dermal Institute, adds that vitamin C is a powerful antioxidant that brightens and protects from free radical damage.

Because vitamin C is so versatile, it’s suitable for use on any skin type. Vitamin C serums come in strengths from as little as 1 percent all the way up to 20 percent. Those with sensitive skin are better off starting low until they build up a tolerance, explains Dr. Eva Simmons-O’Brien, FAAD. She also points out that a serum that mixes vitamins C and E is a good option for reactive skin.

While vitamin C is definitely a hero ingredient, it can also be highly unstable and can easily deactivate before reaching your skin, states Vitabrid C¹²‘s Research Director Jinwoo Kim. In other words, it breaks down quickly and becomes less potent, so we don’t get the major results it’s capable of producing. This is why many vitamin C products are stored in dark bottles or special packaging to prevent oxidization. Furthermore, vitamin C is water soluble, which means it can be tricky for the product to penetrate through the layers of skin that are protected by a lipid layer.

All hope is not lost because the beauty industry has been working to stabilize the notoriously difficult vitamin. Now, there are a lot of fantastic vitamin C products that allow users to enjoy its full benefits. Read on for the best vitamin C serums on the market today.